Unless otherwise indicated herein, the materials described in this section are not prior art to the claims in this application and are not admitted to be prior art by inclusion in this section.
A supercritical fluid may form when a substance, such as water, may reach a pressure and temperature above its critical paint. Supercritical water may occur at pressures higher than 218 atm and temperatures above 374° C. One example application of supercritical water is in treating biomass with supercritical water and in the absence of added oxidants, which may convert organic material into fuel gases.
Applications and devices that use supercritical water may suffer from severe corrosion. Supercritical water gasification (SCWG) is one application that may be prone to corrosion because of the use of coal or similar materials in the process. Coal, tar, or oil, which includes impure hydrocarbons, may lead to the dissolution of highly reactive chemical species at thermodynamic conditions just below the critical point of water. These highly reactive chemical species may increase corrosion rates of the metal walls within the SCWG reactor.